Inside pipe cutter



June 22, 1937. R. D; BRANNON Er A1. '2,084,606

INSIDE PIPE CUTTER Filed sept. 19, 1935 Patented June 22, 1937 PATENT OFFICE INSIDE PIPE CUTTER Robert D. Brannon, Sulphur, La., and Hall G. Moore, Beaumont, Tex.

Application September 19, 1935, Serial No. 41,268

Claims.

This invention relates to an inside pipe cutter.

An object of the invention is to provide a cutter of the character described adapted to cut pipe, in a well bore, by rotation.

5 In well drilling operations the well pipe sometimes becomes stuck in the bore and cannot be withdrawn as a unit and hence must be cut into sections and removed a section at a time. It is an object of this invention to provide ya cutter for that purpose.

Another object of the invention is to provide a pipe cutter of the character described having radially movable blades, or bits, normally held in retracted position and equipped with means capablerof being actuated by the rotation of the operating string to gradually force said blades into active or pipe cutting position and to thereafter automatically release the blades to permit them to move into inactive position after the pipe has been severed,

A further object of the invention is to provide an inside pipe cutter having radially movable cutter blades mounted in a cutter body and norm mally held retracted with an expanding mandrel mounted in the body and gearing also mounted in the body and arranged to be operated by rotation of the operating string to effect 'the expansion of the blades or bits into active or cutting position, said gearing being effective, by

continued rotation of the string, to release the mandrel from the cutters and to permit the cutters to move into inactive position, released from the pipe.

With the above and other objects in view, the

315 invention has particular relation to certain novel features of construction, operation and arrangen ment of parts, an example of which is given in this specification and illustrated in the accompanying drawing, wherein:-

Figure 1 shows a vertical sectional view of the cutter, shown in inactive position in the pipe to be cut.

Figure 2 shows a cross sectional view taken on the line 2--2 of Figure l.

Figure 3 shows a cross sectional View taken on the line 3--3 of Figure l.

Figure 4 shows a cross sectional View taken on the line 4-4'of Figure 1, and

Figure 5 shows a cross sectional view taken on 59 the une s eof Figure 1.

Referring now more particularly to the drawing wherein like numerals of reference designate similar parts in each of the gures, the numerals I,-I designate the complemental sections of the cutter body, said body being cylindrical in general contour. The lower end of the body is reduced and externally threaded to receive the coliar 2 which is screwed thereon to secure the lower ends of the body sections together. The numeral 3 designates the cutter head which is also cy1indrical in general contour and whose lower end is threaded onto the reduced outwardlythreaded upper end of the cutter body whereby the upper ends of the body sections are also secure-d together. Each section of the body has the dowel pins as 4, l as well as the sockets 5, 5, the pins of one section fitting into the sockets of the other to properly align the body sections preparatory to permanently securing them together.

The upper end of the head 3 is connected to an operating string of pipe as 6, which extends to the ground surface and whereby the tool may be operated. The operating string is tubular and flushing iiuid may be forced down through it and this fluid passes on through the channels 1, 'I of the head whereby a cooling and flushing fluid may be supplied to the cutter blades hereinafter referred to.

The head 3 has oppositely disposed longitudi-= nal slots 8, 8 wherein are located the blade carr riers 5, 9 which are pivoted on the cross pins itl, I0. The upper ends of the blade carriers are seated against coil springs I I, I I which hold said upper ends outwardly and the lower ends of the carriers have the outwardly directed blades or bits I2, I2 adapted to out the pipe I3 wherein the cutter is to operate.

At the lower end of the head there is a shaft I5 having an enlarged head IB which is fitted into an internal recess I I in the lower end of the head and this shaft extends axially beneath the head and through an axial bearing I8 in the anchor block I9 beneath. The upper end of the shaft i5 is reduced forming a downwardly facing shoulder 2U which abuts the upper end of the block I9 and screwed onto the lower end of the shaft l5 is the clamp nut 2| which may be screwed up tightly against the block IB whereby said block will be securely clamped on the shaft I5 against turning thereon. The head IE of the bolt I5 is shaped so as to permit the cutter body to turn thereon and the upper end of said head I6 has a polygonal recess 22 therein.

Mounted in the block I9 are the radially movable pipe gripping members 23 whose outer sides are slightly concaved to present sharp edges to the pipe 3 so as to more effectively grip said pipe and the gripping members are held yieldingly in engagement with the pipe by the coil springs 24 against which they are seated.

The upper end of the cutter body has a deep socket in which the conical shaped mandrel E@ is located. This mandrel is fastened to the upper end of the rod 2l which works through the stuffing box 2e in the body and the lower end of the rod 2l is pivotally connected to the upper end of the connecting rod 29. The other end of this rod is eccentrically and pivotally connected to the spur gear 3@ which is fixed on the stub shaft 3l and this stub shaft is mounted to rotate in the bearing 32 in one of the sections i. Beneath the gear 3Q and mounted in suitable end bearings in the sections l, l there is a transverse shaft 33 and xed on this shaft 33 there is a spur gear 34 in mesh with the gear 353 and the worm gear 35, the latter being in mesh with the screw gear SS. This screw gear is xed on a vertical stub shaft 3l whose lower end is tted into, and shaped to conform to, the socket 22.

In operation the cutter is let down into the pipe i3 to the desired point. Thereupon the operating string .6 is rotated causing the head 3 and the cutter body to rotate with it. The anchor block I9 and shaft l5 will be held stationary, or against rotation, by the gripping members fit and the vshaft 3l will also be held stationary. Therefore,

the rotation of the cutter body will impart a I i3. The gear ratio is such that upon the pipe iii being severed the mandrel 2b will start its downward movement and the springs l I will operate to retract the cutters out of contact with the pipe. Thereafter a suitable fishing tool or spear, carried by the operating string, may be engaged with the cut off section and said section removed with the cutter from the well; or when the out is made the cutting tool may be withdrawn and iishing tool lowered into the well and engaged with thev cut off section and the latter removed.

The drawing and description disclose what we now consider to be a preferred form of the invention by way of illustration only, while the broad principle of the invention will be defined by the appended claims.

What we claim is:

l. An inside pipe cutter adapted to cut by rotation and comprising a cutter body, an outwardly movable cutter associated with the body, a mandrel operative against the cutter and movable into one position to effect outward movement of the cutter and into another position to release the cutter, means for moving the cutter inwardly to inactive position upon such release, gearing on the body, means gripping the pipe to be cut and effective to operate the gearing upon rotation of the body and a connecting rod between the gearing and mandrel through which the mandrel is alternately moved to active or released positions.

2. A pipe cutter comprising an anchor, means thereon arranged to grip a pipe in which the cutter is located to hold the anchor against rotation, a rotatable cutter body connected to the anchor, means for rotating said body, outward- Vaosqgeoe ly movable cutters .associated with the body, means normally holding the cutters retracted, a mandrel movable into one position against the cutters to actuate the cutters outwardly into active position and movable into another position to release the cutters to permit retraction thereof, gearing on the body, a connecting rod connecting the gearing and mandrel, and adapted to move the mandrel, and means connected with said anchor and .gearing whereby the gearing is operated upon rotation of the cutter body.

3. A pipe severing device adapted to cut by rotation and shaped to be inserted into a pipe, in a well, to be cut and comprising an anchor, pipegripping means on the anchor, a body rotatable relative to the anchor, gearing housed within the body and operatively connected with the anchor whereby said gearing will be driven upon rotation of the body relative to the anchor, cutting means associated with the body and movable outwardly into cutting relation with the pipe, means normally acting to retract said cutting means into inactive position, a conical shaped actuator having a smooth surface and operatively connected with the gearing and arranged to be actuated thereby into active position to move said cutting means outwardly and into released position to permit retraction of the cutting means, alternately.

4. A pipe severing device adapted to cut by rotation and shaped to be inserted into a pipe, in a well, to be cut and comprising an anchor, pipegripping means on the anchor, a body rotatable relative to the anchor, gearing housed within the body and operatively connected with the anchor whereby said gearing will be driven upon rotation of the body relative to the anchor, cutting means associated with the body and movable outwardly into cutting relation with the pipe, means normally acting to retract said cutting means into inactive position, an `actuator having converging smooth faces and operatively connected with the gearing and arranged to be actuated thereby into active position to move said cutting means outwardly and into released position to permit retraction of the cutting means, alternately, and means connected to the body for rotating the same.

5. A pipe severing device adapted to cut by rotation and shaped to be inserted into a pipe in a well to be cut and comprising an anchor, a cutter body on the anchor, a gear upstanding from the anchor and fixed against rotation relative to the anchor, the body being rotatable relative to the anchor, a train of gearing housed within the body and in operative connection with said gear whereby said train will be driven upon rotation of the body relative to the anchor, cutting means associated with the body and movable outwardly into cutting relation with the pipe, means normally acting to retract the cutting means into active position, an actuator operatively connected with one gear of the train and arranged to be reciprocated longitudinally of the body thereby and having a smooth tapering face effective to move the cutting means outwardly when the actuator is moved in one direction and to permit retraction of the cutting means when the actuator is moved in another direction.

Y ROBERT D. BRANNON.

HALL G. MOORE. 

